It has long been recognized that back pain can be caused or aggravated by extended periods of sitting—either in a chair or in an automobile seat. Left unsupported, the human spine will tend to react gravitationally placing stress on the vertebrae.
Improper sitting posture not only contributes to back pain but also has an impact on other physiological functions, including circulation, respiration, and visceral functions. Current research indicates that the preferred sitting position is one in which the pelvis is tilted back creating an oblique angle between the upper legs and torso. Lumbar support at around L3 has traditionally been recommended to create this angle.
In addition, it is recognized that freedom of movement is important to maintain circulation, and to increase comfort. In an automobile, there are other seating considerations including visibility, ergonomic access to hand and foot controls, mirror visibility, the ability to shoulder check, and safety.
The human spine is commonly considered to have several distinct sections: cervical, thoracic, lumbar, sacral and coccygeal. Past attempts to provide spinal support in a seated position have focussed on particular spinal sections:    lumbar—see U.S. Pat. No. 5,114,209 to Dunn;    thoracic—see U.S. Pat. No. 4,864,668 to Crisp;    cervical—see U.S. Pat. No. 3,156,500 to Kerr; and U.S. Pat. No. 5,248,182 to Hittie.
These partial supports ignore the interconnectedness of the spine and the beneficial effects of supporting the entire spine.
In automobile seating, attention has also been focussed on whiplash prevention. This is not so much a support concern, as it is a barrier concern, to stop the head/neck from hinging backward in the event of a collision or other sudden impact. See, for example, U.S. Pat. No. 2,807,313 to Kaufman; and U.S. Pat. No. 2,990,008 to Bien. However, these whiplash “supports” do not address the rest of the spine.
There have been attempts to support the entire spine, however these are not therapeutically optimal, for several reasons. U.S. Pat. No. 3,454,302 to Radford features an unnatural spinal curve, and the support extends to meet the head and shoulders at an exaggerated angle, which would promote neither comfort nor therapeutic benefit for the user. U.S. Pat. No. 3,361,471 to Radford fails to provide head support above the neck curve.
A chair design put forward by the Steelcase Corporation (the LEAP™ Chair) offers a chair with a useful degree of mobility and may, in some models, extend all the way up to meet the head. However, the chair does not include lateral support.
Another chair design put forward by Mr. John Gorman of the Iliac Vehicle Seat Company (UK) identifies the need for an iliac support in providing spinal support in automotive seating, however, the Iliac Vehicle Seat design does not provide for a lateral support coupled with lumbar support.
There is an outstanding need for a support that traces the entire spine, in addition to providing iliac support. In automotive use, lateral iliac support has the advantage of supporting the hips to stabilize the entire spinal column. It has also been identified that hip support is critical in providing adaptive seating for older persons. Too much weight placed over the hips, without adequate lateral support, can cause pressure and scrubbing of the bone against the tissue at the base of the hips. This tissue becomes thinner as people age. See J. A. Koncelik, “Designing Seating for an Aging Population”, Center for Assistive Technology and Environmental Access, Georgia Institute of Technology.